Abstract 2916: Serial Monitoring of Plasma B-Type Natriuretic Peptide Levels in Outpatients with Heart Failure May Improve Quality of Life
INTRODUCTION: Plasma B-type Natriuretic Peptide (BNP) levels are used to aid in the diagnosis and assessment of severity of heart failure (HF). Pilot data suggests serial BNP measurements may be useful in guiding therapy in outpatients with HF.
HYPOTHESIS: We assessed the hypothesis that monitoring serial BNP levels in outpatients discharged after a hospitalization for HF would improve clinical outcomes.
METHODS: A cluster-randomized study was performed at 31 clinical centers. At 17 centers, serial BNP levels were obtained at 3–14 days, 6 weeks and 3, 6, 9 and 12 months after hospital discharge to guide outpatient management (BNP-M arm) as deemed appropriate by the attending cardiologist; no specific guidelines for HF treatment were mandated by the study protocol. At the other 14 sites, BNP levels were obtained at the same time points in a blinded manner such that results were not available for patient management (Control Arm). Patients were assessed at 3–14 days, 6 months and 12 months following hospital discharge for mortality, interim unplanned hospital visits, need for IV HF therapy, 6-minute walk, NYHA Class and quality of life (QOL) with the Minnesota Living with Heart Failure Questionnaire.
RESULTS: Between July 2003 and July 2006, 387 HF patients were enrolled (223 in the BNP-M Arm and 164 in the Control Arm). The study arms were similar for age, race and baseline HF medications; history of diabetes, angina, cerebrovascular disease and smoking were slightly higher in the Control Arm and systolic dysfunction was slightly higher in the BNP-M Arm. At 12 months follow-up, the primary composite endpoint (of mortality, unplanned hospital visits for HF and change in QOL) tended to be better in the BNP-M Arm than the Control Arm (-0.48 vs. -1.75, T-test p = 0.02) although statistical significance was lost when adjusted for difference in baseline medical history (p = 0.10). Mortality at 12-months was 5.1% vs. 6.5% (p = 0.59) in the BNP-M vs. Control arms. All-cause rehospitalization occurred in 40% of BNP-M patients and 49% of Control Patients (p = 0.09). QOL scores at 12 months were better in the BNP-M Arm vs. the Control Arm (31 vs. 45, p < 0.001).
CONCLUSIONS: Serial monitoring of BNP levels may be useful in minimizing adverse outcomes and maximizing QOL in outpatients with HF.